DS5002FP_1 Datasheet, PDF (11/29 Pages) Dallas Semiconductor – Secure Microprocessor Chip

DS5002FP SERIAL BOOTSTRAP LOADER COMMANDS Table 1
COMMAND
FUNCTION
C
Return CRC-16 of the program/data NV RAM
D
Dump Intel Hex file
F
Fill program/data NV RAM
G
Get data from P1, P2, and P3
I
N/A on the DS5002FP
L
Load Intel Hex file
M
Toggle modem available bit
N
Set Freshness Seal - All program and data will be lost
P
Put data into P0, P1, P2, and P3
R
Read status of NVSFRs (MCON, RPCTL, MSL, CALIB)
T
Trace (echo) incoming Intel Hex code
U
Clear Security Lock
V
Verify program/data NV RAM with incoming Intel Hex data
W
Write Special Function Registers - (MCON, RPCTL, MSL, CALIB)
Z
Set Security Lock
DS5002FP
Execution of certain Bootstrap Loader commands will result in the loading of the newly generated 64-bit
random number into the Encryption Key word. These commands are as follows:
Fill
F
Load
L
Dump
D
Verify
V
CRC
C
Execution of the Fill and Load commands will result in the data loaded into the NV RAM in an encrypted
form determined by the value of the newly-generated key word. The subsequent execution of the Dump
command within the same bootstrap session will cause the contents of the encrypted RAM to be read out
and transmitted back to the host PC in decrypted form. Similarly, execution of the Verify command
within the same bootstrap session will cause the incoming absolute hex data to be compared against the
true contents of the encrypted RAM, and the CRC command will return the CRC value calculated from
the true contents of the encrypted RAM. As long as any of the above commands are executed within the
same bootstrap session, the loaded key value will remain the same and contents of the encrypted
program/data NV RAM may be read or written normally and freely until the Security Lock bit is set.
When the Security Lock bit is set using the Z command, no further access to the true RAM contents is
possible using any bootstrap command or by any other means.
INSTRUCTION SET
The DS5002FP executes an instruction set that is object code-compatible with the industry standard 8051
microcontroller. As a result, software development packages such as assemblers and compilers that have
been written for the 8051 are compatible with the DS5002FP. A complete description of the instruction
set and operation are provided in the User’s Guide section of the Secure Microcontroller Data Book.
Also note that the DS5002FP is embodied in the DS2252T module. The DS2252T combines the
DS5002FP with between 32k and 128k of SRAM, a lithium cell, and a real time clock. This is packaged
in a 40-pin SIMM module.
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